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2.0
VSS_I2C
SCL
25
24
SDA
VSS
23
26
27
22
VSS
VDD_I2C
VDD
SDRAM_17
28
21
VSS
SDRAM_16
29
20
SDRAM_9
VDD
SDRAM_8
VDD
30
19
VSS
31
18
SDRAM_7
32
33
SDRAM_10
VSS
34
SDRAM_11
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
(reserved)
(reserved)
VDD
SDRAM_0
SDRAM_1
VSS
VDD
SDRAM_2
SDRAM_3
VSS
CLK_IN
VDD
SDRAM_4
SDRAM_5
VSS
VDD
SDRAM_6
VSS
VDD
18
35
OE
1
SDRAM_(0:1)
SDRAM_(2:3)
48-pin SSOP
SDRAM_(4:5)
SCL
15
VSS_I2C
16
23
VSS
SDRAM_13
24
SDRAM_17
VDD
25
17
VSS
26
18
SDRAM_14
27
VDD
SDRAM_15
28
19
VDD
SDRAM_(10:11)
20
VSS
VDD
SDRAM_(8:9)
OE
Figure 3: Pin Configuration (FS6051)
VSS
VDD
VSS
SDRAM_(6:7)
CLK_IN
21
VSS
VDD
VSS_I2C
SDRAM_12
SCL
22
Serial
Interface
VDD
VSS
38
VDD
VSS
VDD
SDA
36
SDRAM_12
39
FS6050
Figure 1: Block Diagram (FS6050)
VDD_I2C
37
SDRAM_13
Figure 2: Pin Configuration (FS6050)
40
FS6050: 18 clock outputs in a 48-pin SSOP
FS6051: 10 clock outputs in a 28-pin SOIC, SSOP
FS6053: 13 clock outputs in a 28-pin SOIC
FS6054: 14 clock outputs in a 28-pin SOIC
41
•
•
•
•
VSS
•
2
VDD
Serial interface I/O meet I C specifications; all other
I/O are LVTTL/LVCMOS-compatible
Five differerent pin configurations available:
42
•
SDRAM_14
Less than 5ns propagation delay
Output impedance: 17Ω at 0.5VDD
43
Clock outputs skew-matched to less than 250ps
•
•
SDRAM_15
•
44
Output enable pin tristates all clock outputs to facilitate board testing
VDD
•
45
Supports up to four SDRAM DIMMs
2
Uses either I C-bus or SMBus serial interface with
Read and Write capability for individual clock output
control
(reserved)
•
•
The FS6050 family of CMOS clock fanout buffer ICs are
designed for high-speed motherboard applications, such
®
as Intel Pentium II PC100-based systems with 100MHz
SDRAM.
Up to eighteen buffered, non-inverting clock outputs are
fanned-out from one clock input. Individual clocks are
skew matched to less than 250ps at 100MHz. Multiple
power and ground supplies reduce the effects of supply
noise on device performance.
2
Under I C-bus control, individual clock outputs may be
turned on or off. An active-low output enable is available
to force all the clock outputs to a tristate level for system
testing.
46
Generates up to eighteen low-skew, non-inverting
clocks from one clock input
(reserved)
•
Description
47
Features
48
1.0
VSS
VDD
SDRAM_(12:13)
FS6051
SDRAM_17
VSS
4
5
6
7
8
9
10
11
12
13
14
VDD
SDRAM_2
SDRAM_3
VSS
CLK_IN
VDD
SDRAM_16
VSS
VDD_I2C
SDA
3
VSS
SDRAM_1
VSS
VDD
2
SDRAM_16
OE
SDRAM_0
VSS
VDD
1
SDRAM_(14:15)
VDD
VSS
VDD
28-pin SOIC, SSOP
FS6050
Additional pin configurations are noted on Page 2.
Intel and Pentium are registered trademarks of Intel Corporation. I2C is a licensed trademark of Philips Electronics, N.V. American Microsystems, Inc. reserves the right to change the detail specifications as may be required to permit improvements in the design of its products.
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Table 1: Pin Descriptions
Key: AI = Analog Input; AO = Analog Output; DI = Digital Input; DIU = Input with Internal Pull-Up; DID = Input with Internal Pull-Down; DIO = Digital Input/Output; DI-3 = Three-Level Digital Input,
DO = Digital Output; P = Power/Ground; # = Active Low pin
PIN (FS6050)
PIN (FS6051)
PIN (FS6053)
PIN (FS6054)
TYPE
NAME
11
25
24
4
5
8
9
13
14
17
18
31
32
35
36
40
41
44
45
21
28
38
3, 7, 12, 16,
20, 29, 33, 37,
42, 46
9
15
14
2
3
6
7
22
23
26
27
11
18
20
9
15
14
2
3
6
7
10
11
18
19
22
23
26
27
12
-
9
15
14
2
3
6
7
10
11
18
19
22
23
26
27
12
17
20
DI
DIU
DIUO
DO
DO
DO
DO
DO
DO
DO
DO
DO
DO
DO
DO
DO
DO
DO
DO
DO
DO
DIU
CLK_IN
SCL
SDA
SDRAM_0
SDRAM_1
SDRAM_2
SDRAM_3
SDRAM_4
SDRAM_5
SDRAM_6
SDRAM_7
SDRAM_8
SDRAM_9
SDRAM_10
SDRAM_11
SDRAM_12
SDRAM_13
SDRAM_14
SDRAM_15
SDRAM_16
SDRAM_17
OE
Output enable tristates all clock outputs when low
1, 5, 10, 19,
24, 28
1, 5, 20, 24,
28
1, 5, 24, 28
P
VDD
3.3V ± 5% power supply for SDRAM clock buffers
23
13
13
13
P
VDD_I2C
3.3V ± 5% power supply for serial communications
6, 10, 15, 19,
22, 27, 30, 34,
39, 43
4, 8, 12, 17,
21, 25
4, 8, 17, 21,
25
4, 8, 21, 25
P
VSS
26
16
16
16
P
VSS_I2C
1, 2, 47, 48
-
-
-
-
(reserved)
Ground for SDRAM clock buffers
Ground for serial communications
Reserved
SCL
15
SDRAM_17
SDRAM_8
VSS_I2C
16
17
SDRAM_9
SDRAM_13
23
18
VDD
24
OE
VSS
25
19
SDRAM_14
26
VSS
SDRAM_15
27
20
VDD
28
SDRAM_12
SCL
21
VSS_I2C
15
22
VSS
16
Figure 5: Pin Configuration (FS6054)
17
VDD
20
SDRAM feedback clock outputs (Byte 2)
SDRAM_9
VSS
21
SDRAM clock outputs (Byte 1)
SDRAM_8
SDRAM_12
22
SDRAM clock outputs (Byte 0)
18
SDRAM_13
23
Clock input for SDRAM clock outputs
Serial clock input
Serial data input/output
19
VSS
VDD
SDRAM_14
26
24
SDRAM_15
27
25
VDD
28
Figure 4: Pin Configuration (FS6053)
DESCRIPTION
FS6054
7
8
9
10
11
12
13
14
VSS
CLK_IN
SDRAM_6
SDRAM_7
SDRAM_16
VDD_I2C
SDA
14
SDA
SDRAM_3
13
VDD_I2C
6
12
SDRAM_16
SDRAM_2
11
SDRAM_7
5
10
SDRAM_6
VDD
9
CLK_IN
4
8
VSS
VSS
7
SDRAM_3
3
6
SDRAM_2
SDRAM_1
5
VDD
2
4
VSS
1
3
SDRAM_1
VDD
2
SDRAM_0
1
VDD
SDRAM_0
FS6053
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3.0
3.2
Programming Information
A logic-one written to a valid bit location turns on the assigned output clock. Likewise, a logic-zero written to a
valid bit location turns off the assigned output clock.
Any unused or reserved register bits should be cleared to
zero.
Serial bits are written to this device in the order shown in
Table 3.
Table 2: Clock Enable
CONTROL INPUTS
CLOCK OUTPUTS (MHz)
OE
SDRAM_0:17
0
tristate
1
CLK_IN
Register Programming
Table 3: Register Summary
3.1
Power-Up Initialization
All outputs are enabled and active upon power-up, and all
output control register bits are initialized to one.
The outputs must be configured at power-up and are not
expected to be configured during normal operation. Inactive outputs are held low and are disabled from switching.
SERIAL BIT
DATA BYTE
CLOCK OUTPUT
0
(MSB)
SDRAM_7
1
SDRAM_6
2
SDRAM_5
3
Byte 0
SDRAM_4
4
SDRAM Control Register 0
SDRAM_3
5
3.1.1 Unused Outputs
Outputs that are not used in versions of this device with a
reduced pinout are still operational internally. To reduce
power dissipation and crosstalk effects from the unloaded
outputs, it is recommended that these outputs be shut off
via the Control Registers.
SDRAM_2
6
SDRAM_1
7
(LSB)
SDRAM_0
8
(MSB)
SDRAM_15
9
SDRAM_14
10
SDRAM_13
11
Byte 1
SDRAM_12
12
SDRAM Control Register 1
SDRAM_11
13
SDRAM_10
14
SDRAM_9
15
(LSB)
SDRAM_8
16
(MSB)
SDRAM_17
17
SDRAM_16
18
Reserved
19
Byte 2
Reserved
20
SDRAM Control Register 2
Reserved
21
Reserved
22
Reserved
23
(LSB)
Reserved
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Table 4: Byte 0 - SDRAM Control Register 0
REGISTER
BIT
CLOCK
OUTPUT
DESCRIPTION
OUTPUT PIN
(FS6050)
OUTPUT PIN
(FS6051)
OUTPUT PIN
(FS6053)
OUTPUT PIN
(FS6054)
7
SDRAM_7
On (1) / Off (0)
Pin 18
-
Pin 11
Pin 11
6
SDRAM_6
On (1) / Off (0)
Pin 17
-
Pin 10
Pin 10
5
SDRAM_5
On (1) / Off (0)
Pin 14
-
-
-
4
SDRAM_4
On (1) / Off (0)
Pin 13
-
-
-
3
SDRAM_3
On (1) / Off (0)
Pin 9
Pin 7
Pin 7
Pin 7
2
SDRAM_2
On (1) / Off (0)
Pin 8
Pin 6
Pin 6
Pin 6
1
SDRAM_1
On (1) / Off (0)
Pin 5
Pin 3
Pin 3
Pin 3
0
SDRAM_0
On (1) / Off (0)
Pin 4
Pin 2
Pin 2
Pin 2
Table 5: Byte 1 - SDRAM Control Register 1
REGISTER
BIT
CLOCK
OUTPUT
DESCRIPTION
OUTPUT PIN
(FS6050)
OUTPUT PIN
(FS6051)
OUTPUT PIN
(FS6053)
OUTPUT PIN
(FS6054)
15
SDRAM_15
On (1) / Off (0)
Pin 45
Pin 27
Pin 27
Pin 27
14
SDRAM_14
On (1) / Off (0)
Pin 44
Pin 26
Pin 26
Pin 26
13
SDRAM_13
On (1) / Off (0)
Pin 41
Pin 23
Pin 23
Pin 23
12
SDRAM_12
On (1) / Off (0)
Pin 40
Pin 22
Pin 22
Pin 22
11
SDRAM_11
On (1) / Off (0)
Pin 36
-
-
-
10
SDRAM_10
On (1) / Off (0)
Pin 35
-
-
-
9
SDRAM_9
On (1) / Off (0)
Pin 32
-
Pin 19
Pin 19
8
SDRAM_8
On (1) / Off (0)
Pin 31
-
Pin 18
Pin 18
Table 6: Byte 2 - SDRAM Control Register 2
REGISTER
BIT
CLOCK
OUTPUT
DESCRIPTION
OUTPUT PIN
(FS6050)
OUTPUT PIN
(FS6051)
OUTPUT PIN
(FS6053)
OUTPUT PIN
(FS6054)
23
SDRAM_17
On (1) / Off (0)
Pin 28
Pin 18
-
Pin 17
22
SDRAM_16
On (1) / Off (0)
Pin 21
Pin 11
Pin 12
Pin 12
21
Reserved (set to 0)
-
-
-
-
20
Reserved (set to 0)
-
-
-
-
19
Reserved (set to 0)
-
-
-
-
18
Reserved (set to 0)
-
-
-
-
17
Reserved (set to 0)
-
-
-
-
16
Reserved (set to 0)
-
-
-
-
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4.0
4.1.4 Data Valid
The state of the SDA line represents valid data if the SDA
line is stable for the duration of the high period of the SCL
line after a START condition occurs. The data on the
SDA line must be changed only during the low period of
the SCL signal. There is one clock pulse per data bit.
Each data transfer is initiated by a START condition and
terminated with a STOP condition. The number of data
bytes transferred between START and STOP conditions
is determined by the master device, and can continue
indefinitely. However, data that is overwritten to the device after the data registers are filled will overflow from
the last register into the first register, then the second,
and so on, in a first-in, first-overwritten fashion.
Dual Serial Interface Control
This integrated circuit is a read/write slave device that
2
supports both the Inter IC Bus (I C-bus) and the System
Management Bus (SMBus) two-wire serial interface protocols. The unique device address that is written to the
device determines whether the part expects to receive
2
SMBus commands or I C commands. Since SMBus is
2
derived from the I C-bus, the protocol for both bus types
is very similar.
In general, the bus has to be controlled by a master device that generates the serial clock SCL, controls bus
access, and generates the START and STOP conditions
while the device works as a slave. Both master and slave
can operate as a transmitter or receiver, but the master
device determines which mode is activated. A device that
sends data onto the bus is defined as the transmitter, and
a device receiving data as the receiver.
Bus logic levels and timing parameters noted herein fol2
low I C-bus convention. Logic levels are based on a percentage of VDD. A logic-one corresponds to a nominal
voltage of VDD, while a logic-zero corresponds to ground
(VSS).
4.1
4.1.5 Acknowledge
When addressed, the receiving device is required to generate an Acknowledge after each byte is received. The
master device must generate an extra clock pulse to coincide with the Acknowledge bit. The acknowledging device must pull the SDA line low during the high period of
the master acknowledge clock pulse. Setup and hold
times must be taken into account.
The master must signal an end of data to the slave by not
generating an acknowledge bit on the last byte that has
been read (clocked) out of the slave. In this case, the
slave must leave the SDA line high to allow the master to
generate a STOP condition.
Bus Conditions
Data transfer on the bus can only be initiated when the
bus is not busy. During the data transfer, the data line
(SDA) must remain stable whenever the clock line (SCL)
is high. Changes in the data line when the clock line is
high is interpreted by the device as a START or STOP
2
condition. Both I C-bus and SMBus protocols define the
following conditions on the bus. Refer to Figure 12: Bus
Timing Data for more information.
4.2
Bus Operation and Commands
All programmable registers can be accessed via the bidirectional two wire digital interface. The device accepts
the Random Register Read/Write and the Sequential
2
Register Read/Write I C commands. The device also
supports the Block Read/Write SMBus commands.
4.1.1 Not Busy
Both the data (SDA) and clock (SCL) lines remain high to
indicate the bus is not busy.
4.2.1 I2C-bus and SMBus Device Addressing
After generating a START condition, the bus master
broadcasts a seven-bit device address followed by a R/W
2
bit. Note that every device on an I C-bus or SMBus must
have a unique address to avoid bus conflicts.
For an SMBus interface, the address of the device is:
4.1.2 START Data Transfer
A high to low transition of the SDA line while the SCL input is high indicates a START condition. All commands to
the device must be preceded by a START condition.
4.1.3 STOP Data Transfer
A low to high transition of the SDA line while SCL is held
high indicates a STOP condition. All commands to the
device must be followed by a STOP condition.
A6
A5
A4
A3
A2
A1
A0
1
1
0
1
0
0
1
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2
For an I C-bus interface, the device can support two de2
vice addresses to permit multiple devices on one I C-bus.
The A2 address bit is ignored and can be set to either a
one or a zero.
2
Therefore, for an I C-bus interface the device address is:
4.2.2
4.2.4 I2C-bus: Sequential Register Write Procedure
Sequential write operations, as shown in Figure 8, allow
the master to write to each register in order. The register
pointer is automatically incremented after each write. This
procedure is more efficient than the Random Register
Write if several registers must be written.
To initiate a write procedure, the R/W bit that is transmit2
ted after the seven-bit I C device address is a logic-low.
This indicates to the addressed slave device that a register address will follow after the slave device acknowledges its device address. The register address is written
into the slave’s address pointer. Following an acknowledge by the slave, the master is allowed to write data up
to the last addressed register before the register address
pointer overflows back to the beginning address. An acknowledge by the device between each byte of data must
occur before the next data byte is sent.
Registers are updated every time the device sends an
acknowledge to the host. The register update does not
wait for the STOP condition to occur. Registers are
therefore updated at different times during a Sequential
Register Write.
4.2.3 I2C-bus: Random Register Read Procedure
Random read operations allow the master to directly read
from any register. To perform a read procedure, as
shown in Figure 7, the R/W bit that is transmitted after the
2
seven-bit I C address is a logic-low, as in the Register
Write procedure. This indicates to the addressed slave
device that a register address will follow after the slave
device acknowledges its device address. The register
address is then written into the slave’s address pointer.
Following an acknowledge by the slave, the master generates a repeated START condition. The repeated
START terminates the write procedure, but not until after
the slave’s address pointer is set. The slave address is
then resent, with the R/W bit set this time to a logic-high,
indicating to the slave that data will be read. The slave
will acknowledge the device address, and then transmits
the eight-bit word. The master does not acknowledge the
transfer but does generate a STOP condition.
4.2.5 I2C-bus: Sequential Register Read Procedure
Sequential read operations allow the master to read from
each register in order. The register pointer is automatically incremented by one after each read. This procedure, as shown in Figure 9, is more efficient than the
Random Register Read if several registers must be read
from.
To perform a read procedure, the R/W bit that is trans2
mitted after the seven-bit I C address is a logic-low, as in
the Register Write procedure. This indicates to the addressed slave device that a register address will follow
after the slave device acknowledges its device address.
The register address is then written into the slave’s address pointer.
Following an acknowledge by the slave, the master generates a repeated START condition. The repeated
START terminates the write procedure, but not until after
the slave’s address pointer is set. The slave address is
then resent, with the R/W bit set this time to a logic-high,
indicating to the slave that data will be read. The slave
will acknowledge the device address, and then transmits
all data starting with the initial addressed register. The
register address pointer will overflow if the initial register
address is larger than zero. After the last byte of data, the
master does not acknowledge the transfer but does generate a STOP condition.
A6
A5
A4
A3
A2
A1
A0
1
0
1
1
X
0
0
I2C-bus: Random Register Write Procedure
Random write operations, as shown in Figure
6, allow the master to directly write to any
register. To initiate a write procedure, the R/W
2
bit that is transmitted after the seven-bit I C
device address is a logic-low. This indicates to the addressed slave device that a register address will follow
after the slave device acknowledges its device address.
The register address is written into the slave’s address
pointer. Following an acknowledge by the slave, the
master is allowed to write eight bits of data into the addressed register. A final acknowledge is returned by the
device, and the master generates a STOP condition.
If either a STOP or a repeated START condition occurs
during a Register Write, the data that has been transferred is ignored.
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Figure 6: Random Register Write Procedure (I2C-bus)
S
DEVICE ADDRESS
W A
7-bit Receive
Device Address
REGISTER ADDRESS
A
Register Address
A P
Data
Acknowledge
START
Command
DATA
Acknowledge
STOP Condition
WRITE Command
From bus host
to device
Acknowledge
From device
to bus host
Figure 7: Random Register Read Procedure (I2C-bus)
S
DEVICE ADDRESS
W A
7-bit Receive
Device Address
REGISTER ADDRESS
A S
DATA
A P
Data
Acknowledge
Repeat START
WRITE Command
From bus host
to device
R A
7-bit Receive
Device Address
Register Address
Acknowledge
START
Command
DEVICE ADDRESS
Acknowledge
STOP Condition
READ Command
NO Acknowledge
From device
to bus host
Figure 8: Sequential Register Write Procedure (I2C-bus)
S
DEVICE ADDRESS
W A
7-bit Receive
Device Address
REGISTER ADDRESS
DATA
Register Address
Acknowledge
START
Command
A
A
DATA
DATA
Data
Data
Acknowledge
A
Acknowledge
Data
Acknowledge
WRITE Command
From bus host
to device
A P
Acknowledge
STOP Command
From device
to bus host
Figure 9: Sequential Register Read Procedure (I2C-bus)
S
DEVICE ADDRESS
7-bit Receive
Device Address
W A
REGISTER ADDRESS
Register Address
Acknowledge
START
Command
WRITE Command
From bus host
to device
A S
DEVICE ADDRESS
R A
7-bit Receive
Device Address
A
DATA
Data
Acknowledge
Repeat START
Acknowledge
DATA
READ Command
A P
Data
Acknowledge
NO Acknowledge
STOP Command
From device
to bus host
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registers, starting by default at Register 0. To perform a
Block Read procedure the R/W bit that is transmitted after the seven-bit SMBus address is a logic-low, as in the
Block Write procedure. The write bit resets the register
address pointer to zero. Following an acknowledge of the
SMBus address and R/W bit by the slave device, a command code is written. It is defined that all eight bits of the
command code must be zero (0).
Following an acknowledge by the slave, the master generates a repeated START condition. The repeated
START terminates the write procedure, but not until after
the slave’s address pointer is set. The slave SMBus address is then resent, with the R/W bit set this time to a
logic-high, indicating to the slave that data will be read.
The slave will acknowledge the device address, and then
will expect a byte count value (which will be ignored).
Following the byte count value, the device will take command of the bus and will transmit all the data beginning
with Register 0. After the last byte of data, the master
does not acknowledge the transfer but does generate a
STOP condition.
If the master does not want to receive all the data, the
master can not acknowledge the last data byte and then
can issue a STOP condition of the next clock.
4.2.6
SMBus: Block Write
The Block Write command permits the
master to write several bytes of data to
sequential registers, starting by default at Register 0. The
Block Write command, as noted in Figure 10, begins with
the seven-bit SMBus device address followed by a logiclow R/W bit to begin a Write command. Following an acknowledge of the SMBus address and R/W bit by the
slave device, a command code is written. It is defined
that all eight bits of the command code must be zero (0).
After the command code of zero and an acknowledge,
the host then issues a byte count that describes the
number of data bytes to be written. According to SMBus
convention, the byte count should be a value between 0
and 32; however this slave device ignores the byte count
value.
Following an acknowledge of the byte count, data bytes
may be written starting with Register 0 and incrementing
sequentially. An acknowledge by the device between
each byte of data must occur before the next data byte is
sent.
SMBus
4.2.7 SMBus: Block Read
The Block Read command, shown in Figure 11, permits
the master to read several bytes of data from sequential
Figure 10: Block Write (SMBus)
S
DEVICE ADDRESS
W A
7-bit Receive
Device Address
A
BYTE COUNT = N
Command Code
A
DATA BYTE 1
Byte Count
WRITE Command
From bus host
to device
DATA BYTE N
Data
Acknowledge
START
Command
A
A P
Data
Acknowledge
Acknowledge
Acknowledge
Acknowledge
STOP Command
From device
to bus host
Figure 11: Block Read (SMBus)
S
DEVICE ADDRESS W A
7-bit Receive
Device Address
A S
Command Code
Acknowledge
START
Command
WRITE Command
From bus host
to device
DEVICE ADDRESS
7-bit Receive
Device Address
Repeat START
Acknowledge
R A
BYTE COUNT = N
Byte Count
Acknowledge
READ Command
A
DATA BYTE 1
Data
Acknowledge
Acknowledge
A
DATA BYTE N
A P
Data
NO Acknowledge
STOP Command
From device
to bus host
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5.0
Electrical Specifications
Table 7: Absolute Maximum Ratings
Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. These conditions represent a stress rating only, and functional operation of the device at
these or any other conditions above the operational limits noted in this specification is not implied. Exposure to maximum rating conditions for extended conditions may affect device performance,
functionality, and reliability.
PARAMETER
Supply Voltage, dc, Clock Buffers (VSS = ground)
SYMBOL
MIN.
MAX.
UNITS
V
VDD
VSS-0.5
7
VDD_I2C
VSS-0.5
7
V
Input Voltage, dc
VI
VSS-0.5
VDD+0.5
V
Output Voltage, dc
VO
VSS-0.5
VDD+0.5
V
Input Clamp Current, dc (VI < 0 or VI > VDD)
IIK
-50
50
mA
Output Clamp Current, dc (VI < 0 or VI > VDD)
IOK
-50
50
mA
Storage Temperature Range (non-condensing)
TS
-65
150
°C
Ambient Temperature Range, Under Bias
TA
-55
125
°C
Junction Temperature
TJ
125
°C
Supply Voltage, dc, Serial Communications
Lead Temperature (soldering, 10s)
Static Discharge Voltage Protection (MIL-STD 883E, Method 3015.7)
260
°C
2
kV
CAUTION: ELECTROSTATIC SENSITIVE DEVICE
Permanent damage resulting in a loss of functionality or performance may occur if this device is subjected to a high-energy electrostatic discharge.
Table 8: Operating Conditions
PARAMETER
Supply Voltage, Clock Buffers
SYMBOL
CONDITIONS/DESCRIPTION
MIN.
TYP.
MAX.
UNITS
V
VDD
3.3V ± 5%
3.135
3.3
3.465
Supply Voltage, Serial Communications
VDD_I2C
3.3V ± 5%
3.135
3.3
3.465
V
Ambient Operating Temperature Range
TA
0
70
°C
Input Frequency
fCLK
0
133
MHz
Output Load Capacitance
CL
30
pF
400
kb/s
Serial Data Transfer Rate
Standard mode
10
100
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Table 9: DC Electrical Specifications
Unless otherwise stated, all power supplies = 3.3V ± 5%, no load on any output, and ambient temperature range TA = 0°C to 70°C. Parameters denoted with an asterisk ( * ) represent nominal
characterization data and are not currently production tested to any specific limits. MIN and MAX characterization data are ± 3σ from typical. Negative currents indicate current flows out of the device.
PARAMETER
SYMBOL
CONDITIONS/DESCRIPTION
MIN.
TYP.
MAX.
UNITS
Overall (FS6050)
Supply Current, Dynamic, with Loaded
Outputs
IDD
fCLK = 100MHz; VDD = 3.47V
180
360
mA
Supply Current, Static
IDDL
Outputs low; VDD = 3.47V
0.75
3
mA
Serial Communication Inputs/Output (SDA, SCL)
High-Level Input Voltage
VIH
Outputs low
2.31
VDD+0.3
V
Low-Level Input Voltage
VIL
Outputs low
VSS-0.3
0.9
V
Hysteresis Voltage *
Vhys
Outputs low
1.0
1
µA
15
µA
V
High-Level Input Current
IIH
-1
Low-Level Input Current (pull-up)
IIL
Outputs low; VIH = 0.4V, VDD = 3.47V.
Note: SDA requires an external pull-up to
drive the data bus.
5
11
Low-Level Output Sink Current (SDA)
IOL
VOL = 0.4V
10
25
mA
Output Enable Input (OE)
High-Level Input Voltage
VIH
2.0
VDD+0.3
Low-Level Input Voltage
VIL
VSS-0.3
0.8
V
High-Level Input Current
IIH
-1
1
µA
Low-Level Input Current (pull-up)
IIL
30
µA
V
VIH = 0.4V; VDD = 3.47V
10
22
V
Clock Input (CLK_IN)
High-Level Input Voltage
VIH
2.0
VDD+0.3
Low-Level Input Voltage
VIL
VSS-0.3
0.8
V
II
-1
1
µA
Input Leakage Current
Clock Outputs (SDRAM_0:17 3.3V Type 4 Clock Buffer)
High-Level Output Source Current
Low-Level Output Sink Current
Output Impedance
IOH min
VDD = 3.135V, VO = 2.0V
IOH max
VDD = 3.465V, VO = 3.135V
IOL min
VDD = 3.135V, VO = 1.0V
IOL max
VDD = 3.465V, VO = 0.4V
-54
-65
-28
54
-46
69
33
53
zOH
VO = 0.5VDD; output driving high
10
17.9
24
zOL
VO = 0.5VDD; output driving low
10
16.3
24
-5
5
mA
mA
Ω
µA
Tristate Output Current
IOZ
Short Circuit Source Current *
IOSH
VO = 0V; shorted for 30s, max.
-106
mA
Short Circuit Sink Current *
IOSL
VO = 3.3V; shorted for 30s, max.
107
mA
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Table 10: AC Timing Specifications
Unless otherwise stated, all power supplies = 3.3V ± 5%, no load on any output, and ambient temperature range TA = 0°C to 70°C. Parameters denoted with an asterisk ( * ) represent nominal
characterization data and are not currently production tested to any specific limits. MIN and MAX characterization data are ± 3σ from typical.
CONDITIONS/DESCRIPTION
CLOCK
(MHz)
PARAMETER
SYMBOL
MIN.
TYP.
Clock Skew, Maximum;
SDRAM_0 to any SDRAM pin *
tskw
Measured on the rising edge at 1.5V;
CL = 20pF
66.67
182
100
228
tPLH(min)
Measured on the rising edge at 1.5V;
CL = 20pF
66.67
3.7
100
3.8
tPLH(max)
Measured on the rising edge at 1.5V;
CL = 30pF
66.67
3.7
100
4.0
Measured on the rising edge at 1.5V;
CL = 20pF
66.67
3.9
100
3.8
Measured on the rising edge at 1.5V;
CL = 30pF
66.67
4.2
100
4.0
66.67
1.0
MAX.
UNITS
Overall
Propagation Delay, Average;
CLK_IN to any SDRAM pin *
tPHL(min)
tPHL(max)
ps
ns
Clock Outputs (SDRAM_0:17 3.3V Type 4 Clock Buffer)
tr(min)
VO = 0.4V to 2.4V; CL = 20pF
Rise Time *
tr(max)
tf(min)
VO = 0.4V to 2.4V; CL = 30pF
VO = 2.4V to 0.4V; CL = 20pF
Fall Time *
tf(max)
VO = 2.4V to 0.4V; CL = 30pF
tKH(min)
VO = 2.4V; CL = 20pF
Clock High Time *
tKH(max)
tKL(min)
VO = 2.4V; CL = 30pF
Tristate Enable Delay *
Tristate Disable Delay *
tPZH
tPLZ
tPHZ
1.2
100
1.0
66.67
1.0
100
0.7
66.67
1.1
100
0.8
66.67
6.5
100
3.8
66.67
6.5
100
3.8
6.5
100
4.6
66.67
6.3
100
4.5
From rising edge to rising edge at
1.5V; CL = 20pF
66.67
49
100
45
From rising edge to rising edge at
1.5V; CL = 30pF
66.67
50
VO = 0.4V; CL = 20pF
VO = 0.4V; CL = 30pF
Duty Cycle *
tPZL
0.9
66.67
66.67
Clock Low Time *
tKL(max)
100
Output tristated to output active; CL = 20pF
Output active to output tristated; CL = 20pF
100
ns
ns
ns
ns
%
46
4.7
4.6
6.3
7.9
ns
ns
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Table 11: Serial Interface Timing Specifications
Unless otherwise stated, all power supplies = 3.3V ± 5%, no load on any output, and ambient temperature range TA = 0°C to 70°C. Parameters denoted with an asterisk ( * ) represent nominal
characterization data and are not currently production tested to any specific limits. MIN and MAX characterization data are ± 3σ from typical.
PARAMETER
SYMBOL
CONDITIONS/DESCRIPTION
SCL
MIN.
MAX.
UNITS
10
400
kHz
Clock frequency
fSCL
Bus free time between STOP and START
tBUF
4.7
µs
Set up time, START (repeated)
tsu:STA
4.7
µs
Hold time, START
thd:STA
4.0
µs
Set up time, data input
tsu:DAT
SDA
250
ns
Hold time, data input
thd:DAT
SDA
300
ns
Output data valid from clock
Minimum delay to bridge undefined region of the falling edge of SCL to avoid unintended START or STOP
tAA
Rise time, data and clock
tr
SDA, SCL
Fall time, data and clock
tf
SDA, SCL
High time, clock
tH
SCL
tL
SCL
Low time, clock
Set up time, STOP
3.5
µs
1000
ns
300
tsu:STO
ns
µs
4.0
4.7
µs
4.0
µs
Figure 12: Bus Timing Data
~
~
SCL
~
~
thd:STA
tsu:STA
tsu:STO
SDA
~
~
ADDRESS OR
DATA VALID
START
DATA CAN
CHANGE
STOP
Figure 13: Data Transfer Sequence
tH
SCL
tr
~
~
tf
tL
tsu:STA
thd:STA
tAA
tAA
~
~
SDA
IN
tsu:DAT
tsu:STO
~
~
thd:DAT
tBUF
SDA
OUT
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Figure 14: SDRAM_0:17 Clock Output (3.3V Type 4 Clock Buffer)
Voltage
(V)
Low Drive Current (mA)
MIN.
TYP.
MAX.
0
0
0
0
0.4
23
34
0.65
35
0.85
Voltage
(V)
High Drive Current (mA)
220
MIN.
TYP.
MAX.
0
-72
-116
-198
53
1
-72
-116
-198
140
52
83
1.4
-68
-110
-188
120
43
65
104
1.5
-67
-107
-184
1
49
74
118
1.65
-64
-103
-177
1.4
61
93
152
1.8
-60
-98
-170
1.5
64
98
159
2
-54
-90
-157
1.65
67
103
168
2.4
-39
-69
-126
200
180
160
100
1.8
70
108
177
2.6
-30
-56
-107
1.95
72
112
184
3.135
0
-15
-46
3.135
72
112
204
3.3
0
-23
112
204
3.465
3.6
0
$
80
P 60
W
40
Q
H 20
U
U
0
X
& -20
W
X -40
S
W
X -60
2
0
0.5
1
1.5
2
2.5
3
3.5
4
-80
-100
-120
-140
-160
MIN.
-180
TYP.
-200
MAX.
-220
30 Ω
50 Ω
2XWSXW9ROWDJH9
90 Ω
Figure 15: DC Measurement Points
Figure 17: Timing Measurement Points
τKP
3.3V
VOH 3.3 = 2.4V
tr
VIH 3.3 = 2.0V
1.5V
tf
2.4V
tKH
1.5V
VIL 3.3 = 0.8V
VOL 3.3 = 0.4V
(device
interface)
tKL
(system
interface)
0.4V
Duty Cycle
VDD
Figure 16: Clock Skew Measurement Point
50%
50%
VSS
1.5V
3.3V
50%
tPLZ
90%
1.5V
VOL
10%
tskw
3.3V
tPZL
VOH
50%
tPHZ
tPHZ
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6.0
Package Information
Table 12: 48-pin SSOP (7.5mm/0.300") Package Dimensions
DIMENSIONS
INCHES
48
MILLIMETERS
MIN.
MAX.
MIN.
MAX.
A
0.095
0.110
2.41
2.79
A1
0.008
0.016
0.203
0.406
A2
0.088
0.092
2.24
2.34
B
0.008
0.0135
0.203
0.343
C
0.005
0.010
0.127
0.254
D
0.620
0.630
15.75
16.00
E
0.292
0.299
7.42
7.59
e
0.025 BSC
E
H
XT
1
ALL RADII:
0.005" TO 0.01"
B
7° typ.
e
0.64 BSC
H
0.400
0.410
10.16
10.41
h
0.010
0.016
0.254
0.410
L
0.024
0.040
0.610
1.02
Θ
0°
8°
0°
8°
A2
D
A
A1
BASE PLANE
C
θ
L
SEATING PLANE
Table 13: 48-pin SSOP (7.5mm/0.300") Package Characteristics
PARAMETER
SYMBOL
CONDITIONS/DESCRIPTION
TYP.
UNITS
93
°C/W
Thermal Impedance, Junction to Free-Air
ΘJA
Air flow = 0 m/s
Lead Inductance, Self
L11
Center lead
3.3
nH
Lead Inductance, Mutual
L12
Center lead to any adjacent lead
1.6
nH
Lead Capacitance, Bulk
C11
Center lead to VSS
0.6
pF
Lead Capacitance, Mutual
C12
Center lead to any adjacent lead
0.2
pF
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Table 14: 28-pin SOIC (7.5mm/0.300") Package Dimensions
DIMENSIONS
INCHES
28
MILLIMETERS
MIN.
MAX.
MIN.
MAX.
A
0.093
0.104
2.35
2.65
A1
0.004
0.012
0.10
0.30
A2
0.08
0.100
2.05
2.55
B
0.013
0.013
0.33
0.51
C
0.009
0.009
0.23
0.32
D
0.697
0.713
17.70
18.10
E
0.291
0.299
7.40
7.60
e
0.05 BSC
E
H
XT
1
ALL RADII:
0.005" TO 0.01"
B
e
7° typ.
h x 45°
1.27 BSC
H
0.393
0.419
10.00
10.65
h
0.010
0.030
0.25
0.75
L
0.016
0.05
0.40
1.27
Θ
0°
8°
0°
8°
A2
D
A1
BASE PLANE
A
C
θ
L
SEATING PLANE
Table 15: 28-pin SOIC (7.5mm/0.300") Package Characteristics
PARAMETER
SYMBOL
CONDITIONS/DESCRIPTION
TYP.
UNITS
80
°C/W
Thermal Impedance, Junction to Free-Air
ΘJA
Air flow = 0 m/s
Lead Inductance, Self
L11
Center lead
2.5
nH
Lead Inductance, Mutual
L12
Center lead to any adjacent lead
0.85
nH
Lead Capacitance, Bulk
C11
Center lead to VSS
0.42
pF
Lead Capacitance, Mutual
C12
Center lead to any adjacent lead
0.08
pF
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Table 16: 28-pin SSOP (5.3mm/0.209") Package Dimensions
DIMENSIONS
INCHES
28
MILLIMETERS
MIN.
MAX.
MIN.
MAX.
A
0.068
0.078
1.73
2.00
A1
0.002
0.008
0.05
0.21
A2
0.066
0.07
1.68
1.78
B
0.01
0.015
0.25
0.38
C
0.005
0.008
0.13
0.20
D
0.396
0.407
10.07
10.33
E
0.205
0.212
5.20
5.38
e
0.028 BSC
E
1
B
ALL RADII:
0.005" TO 0.01"
e
0.65 BSC
H
0.301
0.311
7.65
7.90
L
0.022
0.037
0.55
0.95
Θ
0°
8°
0°
8°
H
XT
A2
D
BASE PLANE
A
7° typ.
C
A1
θ
L
SEATING PLANE
Table 17: 28-pin SSOP (5.3mm/0.209") Package Characteristics
PARAMETER
SYMBOL
CONDITIONS/DESCRIPTION
TYP.
UNITS
97
°C/W
Thermal Impedance, Junction to Free-Air
ΘJA
Air flow = 0 m/s
Lead Inductance, Self
L11
Center lead
2.24
nH
Lead Inductance, Mutual
L12
Center lead to any adjacent lead
0.95
nH
Lead Capacitance, Bulk
C11
Center lead to VSS
0.25
pF
Lead Capacitance, Mutual
C12
Center lead to any adjacent lead
0.07
pF
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7.0
Ordering Information
DEVICE
NUMBER
FS6050
FS6051
FS6053
FS6054
ORDERING
CODE
PACKAGE TYPE
OPERATING
TEMPERATURE RANGE
SHIPPING CONFIGURATION
11257-801
48-pin (7.5mm/0.300”) SSOP
0°C to 70°C (Commercial)
Tape and Reel
11257-811
48-pin (7.5mm/0.300”) SSOP
0°C to 70°C (Commercial)
Tube
11257-802
28-pin (7.5mm/0.300”) SOIC
0°C to 70°C (Commercial)
Tape and Reel
11257-812
28-pin (7.5mm/0.209”) SOIC
0°C to 70°C (Commercial)
Tube
11257-806
28-pin (5.3mm/0.209”) SSOP
0°C to 70°C (Commercial)
Tape and Reel
11257-816
28-pin (5.3mm/0.209”) SSOP
0°C to 70°C (Commercial)
Tube
11257-803
28-pin (7.5mm/0.300”) SOIC
0°C to 70°C (Commercial)
Tape and Reel
11257-813
28-pin (7.5mm/0.300”) SOIC
0°C to 70°C (Commercial)
Tube
11257-804
28-pin (7.5mm/0.300”) SOIC
0°C to 70°C (Commercial)
Tape and Reel
11257-814
28-pin (7.5mm/0.300”) SOIC
0°C to 70°C (Commercial)
Tube
2
Purchase of I C components of American Microsystems, Inc., or one of its sublicensed Associated Companies conveys
2
2
a license under Philips I C Patent Rights to use these components in an I C system, provided that the system conforms
2
to the I C Standard Specification as defined by Philips.
Copyright © 1998 American Microsystems, Inc.
Devices sold by AMI are covered by the warranty and patent indemnification provisions appearing in its Terms of Sale only. AMI
makes no warranty, express, statutory implied or by description, regarding the information set forth herein or regarding the freedom
of the described devices from patent infringement. AMI makes no warranty of merchantability or fitness for any purposes. AMI reserves the right to discontinue production and change specifications and prices at any time and without notice. AMI’s products are
intended for use in commercial applications. Applications requiring extended temperature range, unusual environmental requirements, or high reliability applications, such as military, medical life-support or life-sustaining equipment, are specifically not recommended without additional processing by AMI for such applications.
American Microsystems, Inc., 2300 Buckskin Rd., Pocatello, ID 83201, (208) 233-4690, FAX (208) 234-6796,
WWW Address: http://www.amis.com E-mail: [email protected]
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8.0
Application Information
8.1
Reduction of EMI
Figure 18: Board Layout
CLK GND
VOID
The primary concern when designing the board layout for
this device is the reduction of electromagnetic interference (EMI) generated by the 18 copies of the 100MHz
SDRAM clock. It is assumed the reader is familiar with
basic transmission line theory.
1
48
2
47
RS
4
45
RS
5
44
1000pF
8.1.1 Layout Guidelines
To obtain the best performance, noise should be minimized on the power and ground supplies to the IC. Observe good high-speed board design practices, such as:
 Use multi-layer circuit boards with dedicated low impedance power and ground planes for the device
(denoted as CLK VDD and CLK GND in Figure 18).
The device power and ground planes should be
completely isolated from the motherboard power and
ground planes by a void in the power planes.
 Several low-pass filters using low impedance ferrite
EHDGV DW 0+] DUH UHFRPPHQGHG WR GHFRuple the device power and ground planes from the
motherboard power and ground planes (MB VDD and
MB GND). The beads should span the gap between
the power and ground planes. Seven beads for
power and seven beads for ground are suggested
(14 total) so that the clock rise times (1V/ns) can be
maintained.
 Place 1000pF bypass capacitors as close as possible
to the power pins of the IC. Use RF-quality lowinductance multi-layer ceramic chip capacitors. Six
capacitors is optimal, one on each power/ground
grouping as shown in Figure 18.
 Load similar clock outputs equally, and keep output
loading as light as possible to help reduce clock skew
and power dissipation.
 Use equal-length clock traces that are as short as
possible. Rounded trace corners help reduce reflections and ringing in the clock signal.
 The clock traces must never cross the void area between power/ground planes. Each trace must have a
complete plane (either VDD or GND) under the complete length of the trace.
MB GND
RS
RS
1000pF
RS
8
41
RS
RS
9
40
RS
11
38
RS
13
36
RS
RS
14
35
RS
RS
17
32
RS
18
31
1000pF
1000pF
1000pF
RS
RS
1000pF
RS
21
28
24
25
RS
MB VDD
CLK VDD
Component
Layer
MB GND
CLK GND
MB GND
MB VDD
CLK VDD
MB VDD
Signal Layer
8.1.2 Output Driver Termination
A signal reflection will occur at any point on a PC-board
trace where impedance mismatches exist. Reflections
cause several undesirable effects in high-speed applications, such as an increase in clock jitter and a rise in
electromagnetic emissions from the board. Using a properly designed series termination on each high-speed line
can alleviate these problems by eliminating signal reflections.
Figure 19: Series Termination
zO
DRIVER
RS
LINE
zL
RECEIVE
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pacitance, and the number of connected devices with
their associated input currents.
Control of the clock and data lines is done through open
drain/collector current-sink outputs, and thus requires
external pull-up resistors on both lines. A guideline is
Series termination adds no dc loading to the driver, and
requires less power than other resistive termination
methods. Further, no extra impedance exists from the
signal line to a reference voltage, such as ground.
As shown in Figure 19, the sum of the driver’s output impedance (zO) and the series termination resistance (RS)
must equal the line impedance (zL). That is,
RP <
RS = z L − zO .
where tr is the maximum rise time (minus some margin)
2
and Cbus is the total bus capacitance. Assuming an I C
2
device on each DIMM, an I C controller, the clock buffer,
and two other bus devices results in values in the 5kΩ to
7kΩ range. Use of a series resistor to provide protection
against high voltage spikes on the bus will alter the values for RP.
Note that when the source impedance (zO+RS) is
matched to the line impedance, then by voltage division
the incident wave amplitude is one-half of the full signal
amplitude.
Vi = V
tr
,
2 × Cbus
( z O + RS )
V
=
( z O + RS ) + z L 2
The full signal amplitude may take up to twice as long as
the propagation delay of the line to develop, reducing
noise immunity during the half-amplitude period. Note
also that the voltage at the receive end must add up to a
signal amplitude that meets the receiver switching
thresholds. The slew rate of the signal is also reduced
due to the additional RC delay of the load capacitance
and the line impedance. Also note that the output driver
impedance will vary slightly with the output logic state
(high or low).
Figure 20: Connections to the Serial Bus
RP
SDA
RP
SCL
RS
RS
(optional)
(optional)
RS
Data In
Clock Out
Dynamic Power Dissipation
TRANSMITTER
High-speed clock drivers require careful attention to
power dissipation. Transient power (PT) consumption can
be derived from
Clock In
Data Out
RECEIVER
8.3.1 For More Information
More detailed information on serial bus design can be
2
obtained from SMBus and I C Bus Design, available from
the Intel Corporation at http://www.intel.com.
2
Information on the I C-bus can be found in the document
2
The I C-bus And How To Use It (Including Specifications), available from Philips Semiconductors at
http://www-us2.semiconductors.philips.com.
Additional information on the System Management Bus
can be found in the System Management Bus Specification, available from the Smart Battery System
Implementers’ Forum at http://www.sbs-forum.org.
PT = VDD × C load × f CLK × N SW
2
where Cload is the load capacitance, VDD is the supply
voltage, fCLK is the clock frequency, and Nsw is the
number of switching outputs.
The internal heat (junction temperature, TJ) generated by
the power dissipation can be calculated from
TJ = Θ JA × PT + TA
where ΘJA is the package thermal resistance, TA is the
ambient temperature, and PT is derived above.
8.3
(optional)
Data In
Data Out
8.2
RS
(optional)
Serial Communications
Connection of devices to a standard-mode implementa2
tion of either the I C-bus or the SMBus is similar to that
shown in Figure 20. Selection of the pull-up resistors (RP)
and the optional series resistors (RS) on the SDA and
SCL lines depends on the supply voltage, the bus ca4.5.99
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